PROJECT SUMMARY Behavioral and Community Sciences Core (Core J) Behavioral, psychosocial, and structural (economic, policy, organizational, or other aspects of the environment) factors are of utmost importance in the current era of effective HIV prevention and treatment tools. These tools require uptake, adherence, and sustained engagement in care to be impactful, and there are vulnerable sub- groups in the United States who are still unable to access the full continuum of HIV prevention and care services. The Behavioral and Community Sciences Core of the UAB CFAR, Core J, advances science by: 1) enhancing methodological skills of investigators for the conduct of high-quality behavioral and community sciences research; 2) building capacity for creative collaborations between university researchers and communities; and 3) supporting research on priority topics essential to ending disparities in HIV-related health. These efforts have resulted in an impressive growth of HIV behavioral and community science research at UAB over the past award period, including successful K and R level grants, peer-reviewed publications, and strengthened capacity of HIV researchers and local community-based organizations. Through Core J methodological offerings, we enable HIV researchers to use state-of-the-art methodologies and theories from the fields of behavioral and social sciences to better understand sources of vulnerability and resilience. In addition to continuing Core J training opportunities in qualitative research, mixed methods research, and advanced quantitative analytical techniques, in the next award period we will add new trainings in implementation science, community-based intervention trials, and use of contemporary mobile tools. Core J also promotes use of the methods of Community Engaged Research to ensure that research and interventions meet the needs of affected populations. It is necessary to create linkages and collaborations between researchers and communities and to expand the skills and capacity of both HIV researchers and community- based organizations (CBOs). Core J accomplishes this through forming collaborative networks, organizing community-focused seminars and capacity-building activities for CBOs, and providing logistical support to an innovative grassroots CFAR Engaged Community workgroup. Core J community engagement experts assist HIV researchers with connecting to appropriate community partners, developing and carrying out culturally appropriate recruitment strategies to access hard-to-reach populations, and maintaining meaningful partnerships with community members during implementation of HIV research studies and demonstration projects. Core J's community engagement efforts will be systematically integrated into every component of the 90-90-90 targets, assuring community voices are heard. All of this supports priority target areas for ending HIV including reducing stigma, engaging faith and spiritual communities, addressing behavioral aspects of new HIV prevention and treatment technologies, enhancing adolescent sexual and reproductive health behaviors and outcomes, and elucidating strategies to promote linkage and sustained engagement in HIV care.